Professor Coussios joined Oxford as the first academic appointment in biomedical engineering in 2004 and was elected to the first statutory Chair in Biomedical Engineering in 2011. He served as Director of the Institute of Biomedical Engineering between 2016 and 2025, during which time the Institute grew from 16 to 30 academics and expanded from 4 to 8 strategic research areas. In 2022, he became the founding director of the Podium Institute in Sports Medicine and Technology, supported by a £40m ten‑year partnership between the University and Podium Analytics, creating the world’s first cross‑disciplinary biomedical institute focused on safety in youth, community and female sports.

In 2008, he co‑founded OrganOx Ltd, an Oxford University spin‑out that developed a novel normothermic perfusion device for improved liver and kidney preservation. OrganOx became the largest acquisition, and the first in excess of £1bn, to arise from the University following its purchase by Terumo in October 2025. In 2014, he co‑founded OxSonics Ltd, clinically translating ultrasound‑based technology for enhanced cancer drug delivery to solid tumours. In 2018, he co‑founded OrthoSon Ltd, which is developing a novel injectable bio‑structural gel to restore the intervertebral disc and address lower‑back pain.